Physiologically functional foods or cosmetics containing sphingoglycolipids and processes for their production

ABSTRACT

The present invention relates to functional foods or cosmetics containing sphingoglycolipids and a process of producing the same.

TECHNICAL FIELD

[0001] This invention relates to functional foods and cosmeticscontaining sphingoglycolipids and a method of producing the same.

BACKGROUND ART

[0002] Recent researches have been revealing that some complex lipids,particularly some glycolipids exhibit pronounced physiologicalactivities. For example, it has come to be known that ceramides composedof sphingosine and fatty acids and cerebrosides composed of sphingosine,sugar, and fatty acids are present in the stratum corneum of human skinand serve to prevent evaporation loss of water from the body.Application of the glycolipids to the cosmetics taking advantage of thishigh moisturizing activity and application to pharmaceuticals takingadvantage of elastase inhibitory activity or free radical inhibitoryactivity have advanced.

[0003] Ceramide related substances typified by the sphingoglycolipidshave been supplied as extract from bovine brain, etc. However, since theBSE (bovine spongiform encephalopathy) outbreak in 1986 the supply hasdecreased markedly because of the risk of human infection. The demandfor safe ceramide related substances of plant origin has thus beenincreasing.

[0004] Seeing that ceramide related substances of plant origin are by nomeans inferior to those of animal origin and involve neither sideeffects nor toxicity as has recently been revealed, extraction ofceramide related substances from plant raw materials are now underintensive study. Sphingoglycolipids of plant origin, particularlyglycosylceramides, that have hitherto been reported include thoseobtained from cereals and beans, such as rice (see Agric. Biol. Chem.,vol. 49, p. 2753 (1985)), rice bran (see JP-A-62-187404 andJP-A-11-279586), wheat (see Agric. Biol. Chem., vol. 49, 1. 3609 (1985)and a published Japanese translation of a PCT patent application No.Hei.-6-507653), and soybeans (see Chem. Pharm. Bull., vol. 38, No. 11,p. 2933 (1990)).

[0005] Ceramides have been added to skin care products, hair careproducts, bathing preparations, and the like so that the manner oftaking in ceramides has been almost restricted to percutaneousabsorption. In recent years, it has been reported that one-monthadministration of 20 mg/day of wheat extract containing 3 wt % of wheatceramides results in improvement on skin's moisture retention (seeFragrance Journal, vol. 23, No. 1, p. 81 (1995)), and oral intake ofceramides in the form of eatable cosmetics has been attractingattention.

[0006] Cosmetics containing ceramides of animal (horse) origin,ceramides produced by yeast fermentation or synthetic ceramides are nowcommercially available. Being safe, ceramides of plant origin have afavorable image, and many cosmetics featuring the plant origin are onthe market.

[0007] However, plants which have been so far utilized as materials forsupplying plant sphingoglycolipids are limited to cereals and beans, ofwhich the sphingoglycolipids content is not much, usually about 0.01% byweight. All of these plant materials are edible for human consumption,whereas residue after extracting sphingoglycolipids therefrom has novalue as food. The problem of using plants lies in that a vast quantityof food materials lose their value as food only to provide a slightamount of sphingoglycolipids. Looking out over the food processingindustry, on the other hand, it is noted that 3,000 to 4,000 tons of“tobiko” powder occurs a year as a by-product in making konjac products(devil's tongue) from konjac (elephant foot or Amorphophallus konjac).Tobiko powder finds no use as a food due to its peculiar acrid taste andirritating smell, except that part of tobiko powder is made use of as afertilizer or a concrete thickener. Further, cotton seed oil cake, whichis a by-product in squeezing cotton seed to obtain cotton seed oil, hadbeen used as an animal feed rich in vegetable protein until 10 yearsago. However, giving cow cotton seed as a high-energy feed is increasingamong dairy farmers aiming to improve fat content in milk. Increase ofutility of cotton seed oil cake is therefore demanded.

[0008] The present invention relates to functional foods and cosmeticscontaining sphingoglycolipids of plant origin which are attractingattention as a functional material of cosmetics and foods. It is anobject of the present invention to provide functional foods andcosmetics made of materials of plant origin which are rid of the safetyproblem often pointed out in relation to the conventional materialsextracted from animal tissue and yet find no value as food for the timebeing.

DISCLOSURE OF THE INVENTION

[0009] The present inventors have sought for plant raw materialscontaining sphingoglycolipids in a higher concentration than theconventionally used plant raw materials such as cereals and beans. As aresult, they have unexpectedly found out that natural resources of plantorigin, such as tuberous and corm vegetables (e.g., tobiko powder (flypowder) by-produced in making konjac (Amorphophallus konjac) products),and oil cakes (e.g., cotton seed oil cake), contain sphingoglycolipidsin concentrations comparable to or higher than those in cereal and beancrops and completed the present invention. More specifically, they havefound that tuberous and corm vegetables including sweet potato and whitepotato as well as konjac tobiko powder, which occurs in quantity inmaking konjac products and is of little utility value as food, and oilcakes such as cotton seed oil cake are rich in sphingoglycolipids,particularly cerebrosides; that these components can be extractedefficiently from the above-mentioned natural resources by using organicsolvents; and that foods or cosmetics containing the extract exhibithigher moisture retaining action than those containing conventionalsphingoglycolipids of plant (cereal) origin. The present invention hasbeen reached based on these findings.

[0010] A first aspect of the invention consists in functional foodscharacterized by containing sphingoglycolipids derived from tuberous andcorm vegetables, preferably konjac, or oil cakes.

[0011] A second aspect of the invention consists in functional foodscontaining sphingoglycolipids and plant sterols. Preferably thesphingoglycolipids are those extracted from tuberous and cormvegetables, particularly konjac, or oil cakes.

[0012] A third aspect of the invention resides in cosmeticscharacterized by containing sphingoglycolipids derived from tuberous andcorm vegetables, preferably konjac, or oil cakes.

[0013] A fourth aspect of the invention lies in a method of producingsphingoglycolipids-containing products, functional foods or cosmeticscharacterized by comprising adding an organic solvent to a tuberous andcorm vegetable or oil cake and extracting sphingoglycolipids.

BEST MODE FOR CARRYING OUT THE INVENTION

[0014] The present invention will be hereinafter described in detail.

[0015] The plants which can be used as raw materials in the presentinvention include any kind of tuberous and corm vegetables and oilcakes, such as sweet potato, white potato, taro, yam, konjac, long yam,cotton seed oil cake, rapeseed oil cake, coconut oil cake, and palm oilcake. They can be used either as such or after processed by drying,grinding, heating or a like operation. Preferred of them is konjac.Konjac tobiko powder is particularly preferred because it is to bediscarded in quantity and is easily available.

[0016] The sphingoglycolipids which can be used in the invention can beobtained by, for example, extraction from the above-recited plant rawmaterials with an organic solvent as follows.

[0017] Any organic solvents can be used as an extracting solvent as longas they are not reactive on the raw material and sphingoglycolipidsduring extraction and do not impair the effects of the presentinvention. The solvents can be used either individually or as a mixtureof two or more thereof. Such organic solvents include alcohols, such asmethanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, andtert-butanol; polyhydric alcohols, such as ethylene glycol, propyleneglycol, butylene glycol, and glycerol; ketones, such as acetone andmethyl ethyl ketone; esters, such as methyl acetate and ethyl acetate;ethers, such as tetrahydrofuran and diethyl ether; halogenatedhydrocarbons, such as dichloromethane, dichloroethane, and chloroform;aliphatic hydrocarbons, such as hexane, pentane, and petroleum ether;aromatic hydrocarbons, such as toluene; polyethers, such as polyethyleneglycol; and pyridines. Preferred of them are methanol, ethanol, acetone,and hexane. Methanol and ethanol are particularly preferred. In usingthese polar organic solvents for extraction, extraction efficiency maybe improved by addition of water, additives such as surface activeagents, and the like in amounts that do not impair the effects of theinvention.

[0018] The amount of the organic solvent used for extraction isdesirably about 1 to 30 times, particularly about 1 to 10 times, theplant raw material. With the amount of the organic solvent being notsmaller than this range, distribution of the solvent throughout the rawmaterial is ensured to achieve sufficient extraction. Use of a greateramount of the solvent than this range results in no more improvement inextractability. The amount of the solvent falling within this rangeminimizes the load of solvent removal in the subsequent concentrationstep.

[0019] The extracting temperature depends on the boiling point of thesolvent. In the case of methanol or ethanol, a suitable temperature isfrom room temperature up to 70° C., preferably from about roomtemperature to 60° C. At temperatures not lower than room temperature,the extraction efficiency can be increased. Raising the temperature overthe above range is not so influential on extraction efficiency. Energyconsumption can be reduced at temperatures not higher than the aboverange.

[0020] The extracting time is 10 minutes to 24 hours, preferably 1 to 10hours. The extracting time being not shorter than 10 minutes, extractioncan be carried out more sufficiently. Since an increase ofextractability is not expected with a longer time than 24 hours, theabove time range ensures completion of extraction in a minimized time.

[0021] The extraction operation is not limited to a single batchoperation. A fresh solvent may be added to the raffinate to repeatextraction, or an extracting solvent may be brought into contact withthe feed a plurality of times. That is, the extraction operation can becarried out in any of a batch process, a semi-continuous process, and acountercurrent multistage process. Known extraction processes such asSoxhlet extraction may be used.

[0022] The extraction residue is then separated. Methods of separationare not particularly limited. Known methods, such as filtration bysuction, pressure filtration using a filter press or a cylinder press,decantation, centrifugation, and centrifugal filtration, can beemployed.

[0023] The extract thus obtained is preferably sent to a concentrationstep. The method of concentration is not particularly limited. Forexample, the extract is concentrated by means of a vacuum concentrationapparatus, such as an evaporator, or a centrifugal thin film evaporator,such as Evapol (from Ohkawara Seisakusho) or by heating to remove thesolvent.

[0024] The resulting concentrate can be used as such or, if necessary,be purified in a conventional manner to remove impurities and increasethe purity. Useful purification procedures include washing with water,washing with hexane, passing through a silica gel column, a resincolumn, a reversed-phase column, etc., partitioning between solventshaving different polarities, and recrystallization. Where obtaininghighly pure sphingoglycolipids is particularly needed, purification ispreferably conducted by treating the concentrate with an alkalinesolution, partitioning with chloroform, diethyl ether, etc., collectingand concentrating the organic layer, and separating thesphingoglycolipids by column chromatography on silica gel.

[0025] The sphingoglycolipids in the resulting concentrate are analyzedmost conveniently by thin layer chromatography using commerciallyavailable sphingoglycolipids, especially glucosylceramide as a standard.The concentrate is applied on a silica gel thin layer plate anddeveloped with an appropriate solvent system, such as achloroform-methanol system. Visualization of the spots by colordevelopment with concentrated sulfuric acid or an anthrone reagent makesit easy to judge the presence of sphingoglycolipids in the concentratein a high concentration. Presence of sphingoglycolipids in abundance canalso be ascertained by other conventional techniques, such ashigh-performance liquid chromatography and various chromatography/massspectrometries.

[0026] The functional foods as referred to herein are preparations whichcan be orally taken to exert one or more than one effects selected fromskin moisture retention, improvement on skin roughening, skinbeautification, and treatment of atopic dermatitis, allergic dermatitis,psoriasis, pimples, skin aging, hair loss, cancers, AIDS, hypertension,cholesterolemia, arteriosclerosis, and so on. The concentrate may betaken directly as a functional food of the present invention but, foreasy handling, is preferably mixed with carriers and/or diluentsacceptable as food and drink additives and formed into preparationforms, such as powders, tablets, capsules, gels, aqueous dispersions,ethanolic solutions or edible oil solutions.

[0027] Carriers which can be preferably used in powders, tablets orcapsules include dextrin, cyclodextrins, potato starch, corn starch, andlactose. Carriers useful in gels include gelatin, agar, guar gum, gumarabic, and konjac mannan. Water for use in aqueous dispersions is notlimited. Water from springs or deep sea water may be used. The aqueousdispersions can contain saccharides, amino acids, and inorganic salts asfar as the present invention is not ruined. Fruit juice or carbonatedwater is also useful. An emulsifier is preferably added to the aqueousdispersion to help the concentrate be effectively dispersed. Usefulemulsifiers include sucrose fatty acid esters, glycerol fatty acidesters, polyglycerol fatty acid esters, propylene glycol fatty acidesters, and soybean lecithin. Ethanol to be used in the ethanolicsolutions is preferably distilled alcohol. The concentration ofethanolic solutions is not particularly limited. The edible oils to beused in the edible oil solutions are not particularly limited andinclude soybean oil, rapeseed oil, olive oil, sesame oil, safflower oil,and wheat germ oil. In order to effectively disperse the concentrate ofthe invention in edible oil, an emulsifier can be added. Suitableemulsifiers include soybean lecithin, sucrose fatty acid esters,glycerol fatty acid esters, polyglycerol fatty acid esters, andpropylene glycol fatty acid esters.

[0028] The functional foods having the above-described preparation formscan be orally taken alone or as mixed into foods and/or beverages. Thefoods and/or beverages are not particularly limited and include, forexample, staple foods such as bread, wheat noodle, buckwheat noodle, andrice; confectionery, such as cookies, cake, jelly, pudding, candy,chewing gum, and yogurt; liquors; and beverages, such as soft drinks,nutritious drinks, coffee, tea, and milk. In order to promote theeffects, the mixed foods can further contain vitamins, collagen,squalane, soybean lecithin, plant sterols, hyaluronic acid, sorbitol,chitin, chitosan, glucosamine, niacin, niacinamide, Centella asiaticaextract, polyphenols, co-enzyme Q10, pycnojenol, deep sea water, and thelike. In particular, addition of plant sterols is preferred forproducing high effects on skin moisture retention, atopic dermatitis,etc.

[0029] Any kind of plant sterols extracted from plants can be used inthe invention. Specifically, waste such as deodorized scum oil occurringin production of oil, e.g., rice bran oil, cotton seed oil or soybeanoil can be used. They are also extractable from konjac tobiko powder orthe waste from cane sugar factories. β-Sitosterol, campesterol,stigmasterol, sitostanol, campestanol, stigmastanol, and derivativesthereof can be used either individually or as a mixture of two or morethereof. Any derivatives, either synthesized or naturally-occurring, canbe used unless they impair the effects of the invention. Sterolglycosides having sugar bonded, esterified compounds, and compoundshaving an amide linkage are preferred.

[0030] The plant sterols used in the invention can be obtained by knownprocesses. A typical process comprises alkali treatment of deodorizedscum oil which is by-produced in the deodorization step of soybean oilby steam distillation, extraction with an organic solvent, e.g., hexane,and crystallization from a poor solvent, e.g., acetone.

[0031] Commercially available plant sterols for foods as supplied byEisai Co., Ltd. (trade name: Phytosterol F), Tuno Food Industrial Co.,Ltd., etc. are also employable in the present invention.

[0032] Where plant sterols are taken in combination withsphingoglycolipids according to the present invention, thesphingoglycolipids to be combined may be any of synthetic products,fermentation products, and products of animal or plant origin. From thestandpoint of use as a food, those of plant origin which are of highsafety and have been eaten are preferred. Any sphingoglycolipids ofplant origin can be used as far as they are extracted from edibleplants. Preferred are those extracted from cereal crops, such as wheat,wheat bran, barley, rice, rice bran, and corn; beans, such as soybeans;greens, such as spinach, komatuna, and boy choy; tuberous and cormvegetables, such as sweet potato, white potato, taro, yam, konjac, andlong yam; and oil cakes, such as cotton seed oil cake, rapeseed oilcake, coconut oil cake, and palm oil cake. Those extracted from thetuberous and corm vegetables or oil cakes are still preferred. Inparticular, sphingoglycolipids extracted from konjac are the mostpreferred for their high effects.

[0033] Where sphingoglycolipids and plant sterols are mixed into otherfoods and/or beverages, their contents in the mixtures vary according tothe food or food intake and cannot be generally specified but may berepresented in terms of their intakes. An advisable daily intake ofsphingoglycolipids is 1 μg to 100 g, and an advisable daily intake ofplant sterols is 1 mg to 1000 g. The contents in foods are adjusted soas to give such levels of intake.

[0034] The material containing sphingoglycolipids extracted from plantscan be powdered by drying by lyophilization, spray drying, vacuum dryingor a like technique. If necessary, the dried product is ground in asample mill, a speed mill, a blender, a mixer, etc. The resulting powdermay sometimes exhibit viscosity. In such cases, carriers capable ofaccelerating powderization can be added to such an extent that would notdamage the effects of the invention. Such carriers include corn starch,potato starch, dextrin, cyclodextrins, wheat flour, bread crumbs, ediblesalt, zeolite, talc, and oyster shell powder.

[0035] Tablets are prepared by putting the powder preparation obtainedas described above in a tablet machine and punching into tablets. Abinder may be used in such an amount that does not impair the effects ofthe invention.

[0036] Capsules are prepared by putting the powder preparation obtainedas described above and/or a solution preparation into capsules formedicines or foods. Any capsules can be used unless the effects of theinvention are impaired.

[0037] Gels are prepared by any known technique as long as the effectsof the present invention are not ruined. For example, the resultingsphingoglycolipids-containing product is dispersed and/or dissolved inwater, and a conventionally known gelling agent, thickeningpolysaccharide, etc. is added thereto. Gelling agents used for foods,such as gelatin and agar, are used preferably.

[0038] Aqueous dispersions are prepared by stirring thesphingoglycolipids-containing product in a prescribed amount of water.Dispersing may be accelerated by subjecting the system toultrasonication or adding a known emulsifier or dispersant as long asthe effects of the present invention are not damaged.

[0039] Soluble in ethanol, the sphingoglycolipids-containing product issimply dissolved in ethanol to give an ethanolic solution. If desired, astabilizer may be added to the ethanolic solution to preventprecipitation or turbidity within such an amount that does not impairthe effects of the invention.

[0040] Soluble in edible oils, the sphingoglycolipids-containing productcan be directly dissolved in edible oils to provide edible oilsolutions. Where difficult to dissolve, thesphingoglycolipids-containing product is once dissolved in a smallamount of soybean lecithin or egg yolk lecithin and then dissolved in anedible oil to prepare an edible oil solution with ease. In order toprevent precipitation or turbidity, a stabilizer, etc. may be addedwithin such an amount that does not impair the effects of the invention.Further, dissolving can be accelerated by slightly heating the system toreduce the viscosity of the edible oil.

[0041] The edible oils which can be used in the functional foods of theinvention are not particularly limited. Useful edible oils includeanimal fats and oils, such as lard, beef tallow, whale oil, fish oil,and butter; vegetable oils, such as rapeseed oil, soybean oil, oliveoil, rice oil, sunflower oil, and coconut oil; and functionalizedsynthetic oils or mixed oils. They can be used either individually or asa mixture of two or more thereof. Preferred of them are vegetable oilsand health-friendly synthetic oils.

[0042] Made up of components of plant origin, the functional foodsaccording to the present invention have high safety. Therefore, the oralintake and the interval of intake are not particularly limited. Anadvisable daily intake for manifestation of the aimed effects of theinvention is from 1 μg to 100 g in terms of the sphingoglycolipidscontent. It is recommended to maintain taking at a frequency of tentimes a day to once per three days. It is advisable to continue takingfor at least 7 days, preferably 14 days or longer.

[0043] The cosmetics as referred to in the present invention includepreparations which, when applied to the skin or hair, penetrate insideto exert one or more than one effects selected from skin moistureretention, skin whitening, improvements on wrinkles, dark blotches,freckles, and skin roughening, hair growth, prevention of hairsplitting, and treatment of atopic dermatitis, allergic dermatitis,pimples, xeroderma, and the like. Accordingly, the present inventionembraces in its scope a method for treating and/or preventing thesesymptoms which comprises applying the sphingoglycolipids of theinvention in an amount effective on treatment and/or prevention of thesesymptoms. The formula may solely comprise the sphingoglycolipids or be acombination with other cosmetic materials, i.e., cosmetically acceptablecarriers and/or diluents.

[0044] Cosmetically acceptable carriers and/or diluents are notparticularly limited. Examples include colorants, such as titanium mica,talc, silica, and titanium dioxide; oily materials, such as olive oil,castor oil, jojoba oil, bees wax, lanolin, squalane, cetanol, liquidparaffin, methylpolysiloxane, silicone polyether copolymers, and behenylalcohol; humectants, such as glycerol, hyaluronic acid, sorbitol,propylene glycol, dipropylene glycol, chitin, and chitosan; surfaceactive agents, such as alkylsulfates and alkyl ether sulfates;emulsifiers, such as sucrose fatty acid esters, polyglycerol fatty acidesters, sorbitan fatty acid esters, lecithin, polyoxyethylene alkylethers, and alkyl glucosides; vegetable gum or water-soluble polymers,such as quince seed gum, xanthan gum, sodium carboxymethyl cellulose(CMC), carboxyvinyl polymers, polyvinylpyrrolidone, and polyvinylalcohol; water; and ethanol.

[0045] The form is not restricted. For example, the cosmetics can beapplied to the skin in the form of lotions, emulsions, moisture creams,sunscreens, anti-sunburn cosmetics, face packs, foundations, finishingpowders, rouge, eye make-ups, perfumes, eau-de-colognes, lip creams,lipsticks, etc.; or to the hair in the form of hair growth products,pomade, setting lotions, hair sprays, hair dyes, hair tonics, eyelashcosmetics, etc. The formula can be added to facial cleansing creams,facial soaps, shampoos, hair conditioners, hair treatments, bathingpreparations, and the like.

[0046] The method for extracting sphingoglycolipids to be incorporatedinto the cosmetics of the invention is the same as for extractingsphingoglycolipids to be incorporated into the functional foods. Thesphingoglycolipids as extracted may be applied directly as cosmetics ofthe invention. For easier handling, the extract is dissolved in anorganic solvent such as ethanol or dispersed in water.

[0047] Soluble in ethanol, the sphingoglycolipids-containing product issimply dissolved in ethanol to give an ethanolic solution. A stabilizermay be added to the solution to prevent precipitation or turbiditywithin such an amount that does not impair the effects of the invention.

[0048] The aqueous dispersion is prepared by stirring thesphingoglycolipids-containing product in a prescribed amount of water.Dispersing may be accelerated by subjecting the system to heat treatmentor ultrasonication or adding a known emulsifier or dispersant as long asthe effects of the present invention are not damaged. In particular, itis preferred that the sphingoglycolipids-containing product be oncedissolved in an emulsifier, such as soybean or egg yolk lecithin,hydrogenated lecithin and then dispersed in water.

[0049] In order to enhance the effects, the cosmetics of the inventioncan further contain vitamins, collagen, squalane, soybean lecithin,plant sterols, hyaluronic acid, sorbitol, chitin, chitosan, glycerol,butylene glycol, propylene glycol, niacin, niacinamide,galactosylceramide, and so forth.

[0050] Containing the sphingoglycolipids derived from tuberous and cormvegetables or oil cakes, the cosmetics according to the presentinvention are of high safety and may have an unlimitedsphingoglycolipids content. An advisable content of thesphingoglycolipids from tuberous and corm vegetables or oil-cakes formanifestation of the aimed effects of the invention is from 0.001% byweight to 100% by weight. At a content not smaller than 0.001 wt %, theeffects of the invention show up sooner and more sufficiently.

[0051] The typical effects produced when the functional foods orcosmetics of the invention are taken orally or applied to the skin areenhancement of skin moisture retention and improvement on skinroughening. With respect to the skin moisture retention, the effect canbe ascertained through known means such as measurement of transepidermalwater loss (TEWL) or measurement of water content of the stratum corneum(hereinafter referred to as an SC water content). TEWL measurement canbe made with, for example, Evaporimeter from Servo Med, Sweden orTewameter from Courage+Khazaka Electronic GmbH, German. Measurement ofthe SC water content can be taken with, for example, Corneometer fromCourage+Khazaka, German or Skikon 200 from IBS. The effect onimprovement of skin roughening can be seen by observation with the nakedeye and by the user's own feel. The skin whitening effect can also beseen by observation with the naked eye or quantitatively measured with askin color meter Mexameter MX16 from Courage+Khazaka, German.

[0052] The effects produced by the functional foods or cosmetics of theinvention orally taken or applied to the skin owe to the specificactions on the skin of the sphingoglycolipids contained in tuberous andcorm vegetables or oil cakes. Therefore, the functional foods andcosmetics of the invention are superior to those containing thesphingoglycolipids obtained from conventional plant materials, such aswheat, rice bran, and soybeans, particularly in improving effects onskin roughening, atopic dermatitis, allergic dermatitis, and pimples.

EXAMPLES

[0053] The present invention will now be illustrated in greater detailwith reference to Examples, but the present invention is not deemed tobe limited thereto. To begin with, the measuring apparatus and methodsused in Examples are described.

[0054] (1) Qualification of Sphingoglycolipids

[0055] Sphingoglycolipids were qualitatively analyzed by silica gel thinlayer chromatography (TLC). A prescribed amount of a sample was appliedto a silica gel plate (Silicagel 60F254 Type from Merc; layer thickness:0.5 mm), and the plate was placed in a developing chamber containingchloroform:methanol:water (=87:13:2 by volume) to develop the sample.After the development, the silica gel plate was dried with a drier,etc., and sulfuric acid was sprayed thereto followed by heating to causecolor development.

[0056] (2) Quantification of Sphingoglycolipids

[0057] Sphingoglycolipids were quantitatively analyzed byhigh-performance liquid chromatography (HPLC). HPLC was carried out byusing LC Module 1 (from Waters Corp.), a column Inertsil SIL 100A (fromGL Science Inc.), and chloroform:methanol (=9:1 by volume) as a solvent.The measurement was carried out at a flow rate of 1.0 ml/min at 37° C. Ascattered light detector 500 ELSD from Alltech Associates Inc. was usedfor detection.

[0058] (3) Measurement of Stratus Corneum (SC) Water Content

[0059] Corneometer CM825 from Courage+Khazaka was used for SC watercontent measurement. Measurement was always made on the same site 1 cmbelow the left eye. Measurement was taken 10 times for each test personto obtain an average value, which was taken as the datum of that person,and the SC water content was represented as an average of the data fromall test persons.

Example 1 Extraction of Sphingoglycolipids from Konjac Tobiko Powder

[0060] One kilogram of konjac tobiko powder was put into a stirringtank, and 2 liters of ethanol was added, followed by stirring at roomtemperature for 2 hours. The mixture was filtered to separate into anextract and a residue. The extract was concentrated in an evaporator togive 10.7 g of a brown waxy concentrate. The product was analyzed by theabove-described methods for qualification and quantification. TLCrevealed spots corresponding to sphingoglycolipids. The amount of thesphingoglycolipids in the extract was found to be 0.55 g by HPLC. Thepurity of the sphingoglycolipids in the tobiko powder extract was foundto be 5.1 wt %.

Example 2 Extraction of Sphingoglycolipids from Cotton Seed Oil Cake

[0061] One kilogram of cotton seed oil cake was put into a stirringtank, and 2 liters of ethanol was added, followed by stirring at roomtemperature for 5 hours. The mixture was filtered to separate into anextract and a residue. The extract was concentrated in an evaporator togive 8.4 g of a brown waxy concentrate. The product was analyzed by theabove-described methods for qualification and quantification. TLCrevealed spots corresponding to sphingoglycolipids. The amount of thesphingoglycolipids in the extract was found to be 0.41 g by HPLC. Thepurity of the sphingoglycolipids in the cotton seed oil cake extract wasfound to be 4.9 wt %.

Example 3 Extraction of Sphingoglycolipids from Potato Peel

[0062] One kilogram of potato peel grinds (100 μm or smaller particles)was put into a stirring tank, and 2 liters of ethanol was added,followed by stirring at room temperature for 2 hours. The mixture wasfiltered to separate into an extract and a residue. The extract wasconcentrated in an evaporator to give 10.2 g of a yellow waxyconcentrate. The product was analyzed by the above-described methods forqualification and quantification. TLC revealed spots corresponding tosphingoglycolipids. The amount of the sphingoglycolipids in the extractwas found to be 0.42 g by HPLC. The purity of the sphingoglycolipids inthe potato peel extract was 4.1 wt %.

Comparative Example 1 Extraction of Sphingoglycolipids from Wheat Flour

[0063] One kilogram of wheat flour was put into a stirring tank, and 2liters of ethanol was added, followed by stirring at room temperaturefor 5 hours. The mixture was filtered to separate into an extract and aresidue. The extract was concentrated in an evaporator to give 6.8 g ofa deep yellowish brown waxy concentrate. The product was analyzed by theabove-described methods for qualification and quantification. The spotsof sphingoglycolipids appearing in TLC were light in color. The amountof the sphingoglycolipids in the extract was found to be 0.05 g by HPLC.The purity of the sphingoglycolipids in the wheat flour extract was aslow as 0.7 wt %.

Comparative Example 2 Extraction of Sphingoglycolipids from Rice Bran

[0064] One kilogram of defatted rice bran was put into a stirring tank,and 3 liters of ethanol was added, followed by stirring at roomtemperature for 2 hours. The mixture was filtered to separate into anextract and a residue. The extract was concentrated in an evaporator togive 22.3 g of a brown waxy concentrate. The product was analyzed by theabove-described methods for qualification and quantification. As aresult of TLC, the spots of sphingoglycolipids appearing in TLC werelight in color, while the spots corresponding to glyceroglycolipids,sterols, etc. developed deep colors. The amount of thesphingoglycolipids in the extract was found to be 0.38 g by HPLC. Thepurity of the sphingoglycolipids in the defatted rice bran extract was1.7 wt %.

[0065] As described above, the content of sphingoglycolipid componentsin the tobiko powder extract obtained by using an organic solvent is ashigh as 5.1 wt % based on the extract and 0.055 wt % based on the feed.It has now been proved that sphingoglycolipid components are present ina tobiko powder extract in extremely high concentration and purity. Itis also seen that sphingoglycolipid components are present in a potatopeel extract and a cotton seed oil cake extract in sufficiently highconcentration and purity as compared with the conventionally employedfeeds for extraction, i.e., wheat flour and rice bran. Thus, the presentinvention is successful in recovering sphingoglycolipids from tuberousand corm vegetables and oil cakes in extremely high concentrations.

Example 4 Preparation of Powdered Functional Food

[0066] In 20.0 g of ethanol was dissolved 10.0 g of the konjac tobikopowder extract obtained in Example 1, and the solution was introducedinto 200 g of water while stirring. The mixture was further stirredwhile in a dispersed state. Thirty minutes later, 5.0 g of sodiumchloride was added, and the stirring was continued for an additional 10minute period to give a brown precipitate, which weighed 6.8 g. Thesphingoglycolipids content was 0.45 g as measured by HPLC. The extractwas washed with water to have the sphingoglycolipids purity increased to6.6 wt %. The washing operation was repeated once more to give 6.4 g ofa precipitate (designated precipitate A) containing sphingoglycolipidsof konjac tobiko powder origin. The sphingoglycolipids content was foundto be 0.44 g as a result of HPLC. The purity of the sphingoglycolipidsincreased up to 6.9 wt % by washing twice.

[0067] In 15 ml of ethanol was dissolved 5.0 g of precipitate A, and theresulting ethanolic solution was poured into a suspension of 15.0 g ofcorn starch in 50 ml of water while stirring, and the suspension washeated in a boiling water bath for 5 minutes while stirring. As the cornstarch was dissolved and swollen, the suspension increased its viscosityand became pasty. The resulting pasty composition was dried in a vacuumdrier at 50° C. for 12 hours to give a milky white solid, which wasground in a blender to obtain 19.3 g of a powdered functional foodcontaining sphingoglycolipids of konjac tobiko powder origin. Theresulting powder was soaked in ethanol, and the soluble components thusdissolved out were analyzed by TLC. Spots of sphingoglycolipids wereclearly observed.

Example 5 Preparation of Powdered Functional Food

[0068] In 15 ml of ethanol was dissolved 5.0 g of precipitate A ofExample 4. The resulting ethanolic solution was poured into a suspensionof 10.0 g of β-cyclodextrin in 20 ml of water while stirring. Asstirring was continued, the suspension increased its viscosity andbecame pasty. The resulting pasty composition was dried in a vacuumdrier at 50° C. for 12 hours to give a milky white solid, which wasground in a blender to obtain 14.8 g of a powdered functional foodcontaining sphingoglycolipids of konjac tobiko powder origin. Theresulting powder was soaked in ethanol, and the soluble components thusdissolved out were analyzed by TLC. Spots of sphingoglycolipids wereclearly observed.

Example 6 Preparation of Powdered Functional Food

[0069] In 15 ml of ethanol was dissolved 5.0 g of precipitate A ofExample 4. The resulting ethanolic solution was poured into a suspensionof 15.0 g of corn starch in 50 ml of water while stirring, and thesuspension was heated in a boiling water bath for 5 minutes whilestirring. As the corn starch was dissolved and swollen, the suspensionincreased its viscosity and became pasty. To the resulting pastycomposition was added 450 ml of water, followed by stirring to obtain alow-viscosity dispersion. The dispersion was delivered to a spray drier(Spray Dryer LT-8, manufactured by Ohkawara Kakoki K.K.) at a rate of31/min and powdered under conditions of an inlet temperature of 250° C.,an outlet temperature of 150° C., and an atomizer revolution speed of35000 rpm. The resulting powdered functional food containingsphingoglycolipids of konjac tobiko powder origin weighed 18.7 g andassumed a light brown color. The resulting powder was soaked in ethanol,and the soluble components thus dissolved out were analyzed by TLC.Spots of sphingoglycolipids were clearly observed.

Example 7 Preparation of Functional Food in Aqueous Dispersion Form

[0070] In 500 ml of water were put 5.0 g of precipitate A of Example 4and 2.5 g of decaglycerol monostearate (SY Glyster MSW-750, availablefrom Sakamoto Yakuhin Kogyo Co., Ltd.) and dispersed by ultrasonicationusing BRANSON 3200, available from Yamato Scientific Co., Ltd., for 30minutes. There was obtained a functional food of aqueous dispersion formcontaining sphingoglycolipids of konjac tobiko powder origin. Theresulting aqueous dispersion was uniform and generated no sediment on 3months' standing.

Example 8 Preparation of Gelatinous Functional Food

[0071] In 15 ml of ethanol was dissolved 5.0 g of precipitate A ofExample 4. The resulting ethanolic solution was poured into a solutionof 15.0 g of gelatin in 20 ml of water heated at 60° C. while stirring.The solution was allowed to cool to room temperature whereupon it turnedinto an ocherous hard gel. There was thus obtained a gelatinousfunctional food containing sphingoglycolipids of konjac tobiko powderorigin.

Comparative Example 3 Preparation of Food Containing Sphingoglycolipidsof Wheat Flour Origin

[0072] In 10.0 g of ethanol was dissolved 5.0 g of the wheat flourextract obtained in Comparative Example 1, and the solution wasintroduced into 100 g of water while stirring. The mixture was furtherstirred while in a dispersed state. Thirty minutes later, 2.5 g ofsodium chloride was added, and the stirring was continued for anadditional 10 minute period to give a brown precipitate, which weighed3.6 g. The sphingoglycolipids content was 0.04 g as measured by HPLC.After washing with water, the extract had a sphingoglycolipids purity of1.1 wt %. The washing operation was repeated once more to give 3.4 g ofa precipitate containing sphingoglycolipids of wheat flour origin. Thesphingoglycolipids content was found to be 0.04 g as a result of HPLC.The purity of the sphingoglycolipids obtained after washing twice was1.2 wt %.

[0073] In 300 ml of water were put 3.0 g of the precipitate and 1.5 g ofdecaglycerol monostearate (SY Glyster MSW-750, available from SakamotoYakuhin Kogyo Co., Ltd.), and the mixture was treated in the same manneras in Example 7 to obtain an aqueous dispersion containingsphingoglycolipids of wheat flour origin.

Comparative Example 4 Preparation of Food Containing Sphingoglycolipidsof Rice Bran Origin

[0074] In 20.0 g of ethanol was dissolved 10.0 g of the rice branextract obtained in Comparative Example 2, and the solution wasintroduced into 200 g of water while stirring. The mixture was furtherstirred while in a dispersed state. Thirty minutes later, 5.0 g ofsodium chloride was added, and the stirring was continued for 10 minutesto give a brown precipitate, which weighed 7.4 g. The sphingoglycolipidscontent was 0.24 g as measured by HPLC. After washing with water, theextract had a sphingoglycolipids purity of 3.2 wt %. The washingoperation was repeated once more to give 6.9 g of a precipitatecontaining sphingoglycolipids of rice bran origin. Thesphingoglycolipids content was found to be 0.22 g as a result of HPLC.The purity of the sphingoglycolipids obtained after washing twice was3.2 wt %.

[0075] In 300 ml of water were put 3.0 g of the precipitate and 1.5 g ofdecaglycerol monostearate (SY Glyster MSW-750, available from SakamotoYakuhin Kogyo Co., Ltd.), and the mixture was treated in the same manneras in Example 7 to obtain an aqueous dispersion containingsphingoglycolipids of rice bran origin.

Test Example 1 Influences on SC Water Content

[0076] The functional food of the present invention obtained in Example7 (aqueous dispersion), the aqueous dispersions obtained in ComparativeExamples 3 and 4, and a dispersion containing no sphingoglycolipids weretested for SC water content improving effects on ten volunteers for eachsex (five persons between the ages of 20 and 40 and five persons betweenthe ages of 40 and 60 for each sex). The dispersion containing nosphingoglycolipids was prepared by dissolving 1.5 g of decaglycerolmonostearate (SY Glyster MSW-750, available from Sakamoto Yakuhin KogyoCo., Ltd.) in 300 ml of water.

[0077] The test persons were asked to take in 1.45 ml/day of thefunctional food of the invention, 8.5 ml/day of the dispersion obtainedin Comparative Example 3, and 3.25 ml/day of the dispersion obtained inComparative Example 4 each for 30 days. These daily intakes correspondto 1 mg of the sphingoglycolipids per day. The dispersion containing nosphingoglycolipids as a control was taken in an amount of 1.45 ml/day.

[0078] The SC water content of the skin 1 cm below the left eye wasmeasured with Corneometer after 10 days, 20 days and 30 days from thefirst day of taking. The average results of the twenty test persons areshown in Table 1. TABLE 1 Initial After 10 After 20 After 30 Value DaysDays Days Example 7 (tobiko powder 44 62 68 73 origin) ComparativeExample 3 47 51 55 58 (wheat flour origin) Comparative Example 4 46 4953 60 (rice bran origin) Control 43 45 47 46

[0079] It is seen from Table 1 that taking sphingoglycolipids of konjactobiko powder origin produces greater effects in improving the skin SCwater content than taking sphingoglycolipids of wheat flour or rice branorigin.

Test Example 5 Improving Effect on Skin Roughening

[0080] The functional food of the present invention obtained in Example7 (aqueous dispersion), the aqueous dispersions obtained in ComparativeExamples 3 and 4, and a dispersion containing no sphingoglycolipids weretested for rough skin improving effects with cooperation of ten femalessuffering from skin roughening on the back of their hands. Thedispersion containing no sphingoglycolipids was prepared by dissolving1.5 g of decaglycerol monostearate (SY Glyster MSW-750, available fromSakamoto Yakuhin Kogyo Co., Ltd.) in 300 ml of water.

[0081] The test persons were asked to take in 1.45 ml/day of thefunctional food of the invention, 8.5 ml/day of the dispersion obtainedin Comparative Example 3, and 3.25 ml/day of the dispersion obtained inComparative Example 4 each for 15 days. These daily intakes correspondto 1 mg of the sphingoglycolipids per day. The dispersion containing nosphingoglycolipids as a control was taken in an amount of 1.45 ml/day.

[0082] Meanwhile they were asked to answer a questionnaire about thecondition of the back of their hands after 5 days, 10 days and 15 days.The results obtained are shown in Table 2 as a total score. TABLE 2After 5 After 10 After 15 Days Days Days Example 7 (tobiko powder 22 2934 origin) Comparative Example 3 (wheat 19 22 29 flour origin)Comparative Example 4 (rice 18 22 27 bran origin) Control  8 13 14

[0083] Answers and Scores:

[0084] 4 . . . The skin roughening was completely healed.

[0085] 3 . . . The skin condition was improved greatly.

[0086] 2 . . . The skin condition was improved.

[0087] 1 . . . The skin condition was unchanged.

[0088] 0 . . . The skin condition got worse.

[0089] It is seen from Table 2 that taking sphingoglycolipids of konjactobiko powder origin brings about more excellent effects of improvingskin roughening than taking sphingoglycolipids of wheat flour or ricebran origin.

Example 9 Preparation of Powdered Functional Food Containing PlantSterols

[0090] Plant sterols of soybean oil origin which mainly compriseβ-sitosterol (2.0 g; Phytosterol F from Eisai Co., Ltd., hereinaftersimply referred to as Phytosterol F) was added to 14.8 g of the powdercontaining sphingoglycolipids of konjac tobiko powder origin obtained inExample 5, and the mixture was stirred well to get uniform to prepare apowdered functional food.

Example 10 Preparation of Plant Sterols-Containing Functional Food ofAqueous Dispersion Form

[0091] Precipitate A of Example 4 (5.0 g) and 2.0 g of Phytosterol Fwere kneaded at 50° C. for 5 minutes to obtain a brown paste. The pastewas put into 500 ml of water together with 2.5 g of decaglycerolmonostearate (SY Glyster MSW-750, available from Sakamoto Yakuhin KogyoCo., Ltd.) and dispersed by ultrasonication using BRANSON 3200,available from Yamato Scientific Co., Ltd., for 30 minutes. Theresulting aqueous dispersion containing sphingoglycolipids and plantsterols was uniform and formed no sediment on 3 months' standing.

Example 11 Preparation of Plant Sterols-Containing Functional Food ofAqueous Dispersion Form

[0092] Precipitate A of Example 4 (1.0 g) and 2.0 g of Phytosterol Fwere kneaded at 50° C. for 5 minutes to obtain a brown paste. The pastewas put into 500 ml of water together with 2.5 g of decaglycerolmonostearate (SY Glyster MSW-750, available from Sakamoto Yakuhin KogyoCo., Ltd.) and dispersed by ultrasonication using BRANSON 3200, 36available from Yamato Scientific Co., Ltd., for 30 minutes. Theresulting aqueous dispersion containing sphingoglycolipids and plantsterols was uniform and generated no sediment on 3 months' standing.

Example 12 Preparation of Plant Sterols-Containing Functional Food ofAqueous Dispersion Form

[0093] An aqueous dispersion containing sphingoglycolipids and plantsterols was prepared in the same manner as in Example 10, except forreplacing Phytosterol F with β-sitostanol (from Sigma). The resultingaqueous dispersion containing sphingoglycolipids and plant sterols wasuniform and generated no sediment on 3 months' standing.

Example 13 Preparation of Plant Sterols-Containing Gelatinous FunctionalFood

[0094] In 15 ml of ethanol was dissolved 5.0 g of precipitate A ofExample 4, and 2.0 g of Phytosterol F was added thereto, followed bystirring at 30° C. for 5 minutes to obtain a solution. The resultingethanolic solution was introduced into an aqueous solution of 15.0 g ofgelatin in 20 ml of water heated at 60° C. while stirring. The solutionwas allowed to cool to room temperature whereupon it turned into anocherous hard gel to give a gelatinous functional food.

Example 14 Preparation of Plant Sterols-Containing Wheat Flour Extract

[0095] The wheat flour extract (3.0 g) obtained in Comparative Example 1and 0.21 g of Phytosterol F were kneaded at 50° C. for 5 minutes toobtain an ocherous paste. The paste was put into 300 ml of watertogether with 1.5 g of decaglycerol monostearate (SY Glyster MSW-750,available from Sakamoto Yakuhin Kogyo Co., Ltd.). The mixture wastreated in the same manner as in Example 10 to obtain an aqueousdispersion containing sphingoglycolipids of wheat flour origin and plantsterols.

Example 15 Preparation of Plant Sterols-Containing Rice Bran Extract

[0096] The rice bran extract (3.0 g) obtained in Comparative Example 2and 0.56 g of Phytosterol F were kneaded at 50° C. for 5 minutes toobtain a brown paste. The paste was put into 300 ml of water togetherwith 1.5 g of decaglycerol monostearate (SY Glyster MSW-750, availablefrom Sakamoto Yakuhin Kogyo Co., Ltd.). The mixture was treated in thesame manner as in Example 10 to obtain an aqueous dispersion containingsphingoglycolipids of rice bran origin and plant sterols.

Comparative Examples 5 to 7

[0097] For comparison, an aqueous dispersion containingsphingoglycolipids of konjac tobiko powder origin was prepared in thesame manner as in Example 10, except that p-sitosterol was not added(Comparative Example 5). In 500 g of water was dispersed 2.0 g ofPhytosterol F with the aid of 2.5 g of decaglycerol monostearate (SYGlyster MSW-750, available from Sakamoto Yakuhin Kogyo Co., Ltd.) as anemulsifier to prepare an aqueous dispersion (Comparative Example 6). Anaqueous solution of 2.5 g of the same decaglycerol monostearate in 500 gof water was prepared (Comparative Example 7).

Test Example 3 Influences on SC Water Content

[0098] Ten volunteers for each sex (five persons between the ages of 20and 40 and five persons between the ages of 40 and 60 for each sex) wereasked to take a prescribed amount of each functional food obtained inExamples for 30 days each. The SC water content of the skin 1 cm belowthe left eye was measured with Corneometer after 10 days, 20 days and 30days. The functional foods and intakes used in the test are shown inTable 3.

[0099] The average results of the twenty test persons are shown in Table3. Table 3 proves that taking the functional foods comprising thesphingoglycolipids of konjac origin and plant sterols produces excellenteffects in improving the skin SC water content. TABLE 3 Daily Intake SCWater Content Sphingo- Initial After 10 After 20 After 30 Foodglycolipids Plant Sterols Value Days Days Days Example 10 aqueousdispersion konjac Phytosterol F 40 57 69 72 1.45 ml 1 mg 5.8 mg Example11 aqueous dispersion konjac Phytosterol F 43 58 66 69 1.45 ml 0.2 mg5.8 mg Example 12 aqueous dispersion konjac β-sitostanol 39 63 70 731.45 ml 1.0 mg 5.8 mg Example 14 aqueous dispersion wheat Phytosterol F42 56 61 64 8.33 ml 1.0 mg 5.8 mg Example 15 aqueous dispersion ricebran Phytosterol F 40 55 63 66 3.13 ml 1.0 mg 5.8 mg Compara. aqueousdispersion konjac — 41 55 60 63 Example 5 1.45 ml 1.0 mg Compara.aqueous dispersion — Phytosterol F 39 42 43 45 Example 6 1.45 ml 5.8 mgCompara. solution — — 38 39 43 40 Example 7 1.45 ml

Test Example 4 Skin Roughening Improving Effects

[0100] Cooperation of ten females suffering from skin roughening on theback of their hands was obtained. The test persons were asked to dailytake in a prescribed amount of each functional food prepared in Examplesfor 15 days. Meanwhile they were asked to answer a questionnaire aboutthe condition of the back of their hands after 5 days, 10 days and 15days. The samples and intakes used are shown in Table 4.

[0101] The results obtained are shown in Table 4 as a total score. It isseen from Table 4 that taking functional foods comprising thesphingoglycolipids of konjac origin and plant sterols produces excellentimproving effects on skin roughening. TABLE 4 Skin Roughening DailyIntake Improving Effects Sphingo- After 5 After 10 After 15 Foodglycolipids Plant Sterols Days Days Days Example 10 aqueous dispersion1.45 ml konjac 1 mg Phytosterol F 5.8 mg 27 30 35 Example 11 aqueousdispersion 1.45 ml konjac 0.2 mg Phytosterol F 5.8 mg 22 28 32 Example12 aqueous dispersion 1.45 ml konjac 1.0 mg β-sitostanol 5.8 mg 25 30 36Example 14 aqueous dispersion 8.33 ml wheat 1.0 mg Phytosterol F 5.8 mg23 25 28 Example 15 aqueous dispersion 3.13 ml rice bran 1.0 mgPhytosterol F 5.8 mg 25 28 30 Compara. aqueous dispersion 1.45 ml konjac1.0 mg — 20 24 26 Example 5 Compara. aqueous dispersion 1.45 ml —Phytosterol F 5.8 mg 10 13 16 Example 6 Compara. solution 1.45 ml — —  812 14 Example 7

[0102] Answers and Scores:

[0103] 4 . . . The skin roughening was completely healed.

[0104] 3 . . . The skin condition was improved greatly.

[0105] 2 . . . The skin condition was improved.

[0106] 1 . . . The skin condition was unchanged.

[0107] 0 . . . The skin condition got worse.

Example 16 Preparation of Cosmetic Containing Sphingoglycolipids ofKonjac Origin

[0108] An ethyl acetate:methanol (=9:1; 200 ml) mixed solvent was passedthrough a column packed with 150 ml of silica gel (Silica Gel 60,available from Nacalai tesque, Inc.; 70 to 230 mesh). When the solventliquid level reached the upper edge of silica gel, and effusion becameslow, 1.9 g of precipitate A of Example 4 dissolved in hexane to make6.0 ml was introduced into the column. Then 400 ml of an ethylacetate:methanol (=9:1) mixed solvent was passed through, and theeffluent was collected in 20 ml fractions. Each fraction was analyzed bythin layer chromatography. The 12th to 17th fractions developed deepspots of sphingoglycolipids. The fractions in this range were combined,and the solvent was removed by evaporation to give 386 mg of a solid.HPLC revealed that the sphingoglycolipids content of the solid was 226mg, indicating that the resulting sphingoglycolipids-containing producthad a sphingoglycolipids concentration of 58.5 wt %.

[0109] An ethyl acetate:methanol (=95:5) mixed solvent (200 ml) waspassed through a column packed with 150 ml of silica gel (Silica Gel 60,available from Nacalai tesque, Inc.; 70 to 230 mesh). When the solventliquid level reached the upper edge of silica gel, and effusion becameslow, 386 mg of the solid prepared above by silica gel columnchromatography and dissolved in a small amount of hexane was introducedinto the column. Then 800 ml of an ethyl acetate:methanol (=95:5) mixedsolvent was passed through, and the effluent was collected in 20 mlfractions. Each fraction was analyzed by thin layer chromatography. Asingle spot of sphingoglycolipids was observed with the 20th to 26thfractions. The fractions in this range were combined, and the solventwas removed by evaporation to give 87 mg of a solid. HPLC revealed thatthe sphingoglycolipids content of the solid was 86 mg, indicating thatthe resulting sphingoglycolipids-containing product had asphingoglycolipids concentration of 98.9 wt %.

[0110] The solid (50.6 mg) was put into 10 ml of water with stirring anddispersed by ultrasonication using BRANSON 3200, available from YamatoScientific Co., Ltd., for 30 minutes to obtain a cosmetic containingsphingoglycolipids of konjac tobiko powder origin according to thepresent invention. The resulting sphingoglycolipids-containing aqueousdispersion was uniform and produced no sediment when allowed to standfor one day. This aqueous dispersion contained 50 mg ofsphingoglycolipids of konjac tobiko powder origin.

Example 17 Preparation of Cosmetic Containing Sphingoglycolipids ofPotato Origin

[0111] Five grams of the potato peel extract obtained in Example 3 wasdissolved in 10.0 g of ethanol, and the solution was introduced into 100g of water while stirring. The mixture was further stirred while in adispersed state. Thirty minutes later, 2.5 g of sodium chloride wasadded, and the stirring was continued for additional 10 minutes to givea light brown precipitate, which weighed 3.0 g. The sphingoglycolipidscontent was 0.18 g as measured by HPLC. After washing with water, theextract had a sphingoglycolipids purity of 6.0 wt %. The washingoperation was repeated once more to give 2.8 g of a precipitate, whichwas found to have a sphingoglycolipids content of 0.18 g as a result ofHPLC. The purity of the sphingoglycolipids obtained after washing twicewas 6.4 wt %. The resulting product containing sphingoglycolipids ofpotato peel origin was purified twice by silica gel columnchromatography in the same manner as in Example 16 to obtain 38 mg of asphingoglycolipids-containing product having a sphingoglycolipidscontent of 96.8 wt %.

[0112] The above-described series of operations were repeated severaltimes. The thus produced product containing sphingoglycolipids of potatopeel origin (51.7 mg) was put into 10 ml of water while stirring anddispersed by 30-minute ultrasonication by use of BRANSON 3200, availablefrom Yamato Scientific Co., Ltd., to obtain a cosmetic containing thesphingoglycolipids of potato peel origin according to the presentinvention. The resulting sphingoglycolipids-containing aqueousdispersion was uniform and generated no sediment after one-day standing.This aqueous dispersion contained 50 mg of sphingoglycolipids of potatopeel origin.

Comparative Example 8 Preparation of Cosmetic ContainingSphingoglycolipids of Wheat Origin

[0113] Five grams of the wheat flour extract obtained in ComparativeExample 1 was dissolved in 10.0 g of ethanol, and the solution wasintroduced into 100 g of water while stirring. The mixture was furtherstirred while in a dispersed state. Thirty minutes later, 2.5 g ofsodium chloride was added, and the stirring was continued for 10 minutesto give a brown precipitate, which weighed 3.6 g. The sphingoglycolipidscontent was 0.04 g as measured by HPLC. After washing with water, theextract had a sphingoglycolipids purity of 1.1 wt %. The washingoperation was repeated once more to give 3.4 g of a precipitate, whichwas found to have a sphingoglycolipids content of 0.04 g as a result ofHPLC. The purity of the sphingoglycolipids obtained after washing twicewas 1.2 wt %. The resulting product containing sphingoglycolipids ofwheat origin was purified twice by silica gel column chromatography inthe same manner as in Example 16 to obtain 2 mg of asphingoglycolipids-containing product having a sphingoglycolipidscontent of 97.5 wt %.

[0114] The above-described series of operations were repeated severaltimes. The thus produced product containing sphingoglycolipids of wheatorigin (51.3 mg) was put into 10 ml of water while stirring anddispersed by 30-minute ultrasonication by use of BRANSON 3200, availablefrom Yamato Scientific Co., Ltd. The resultingsphingoglycolipids-containing aqueous dispersion was uniform andgenerated no sediment after one-day standing. This aqueous dispersioncontained 50 mg of sphingoglycolipids of wheat origin.

Comparative Example 9 Preparation of Cosmetic ContainingSphingoglycolipids of Rice Bran Origin

[0115] Ten grams of the defatted rice bran extract obtained inComparative Example 2 was dissolved in 20.0 g of ethanol, and thesolution was introduced into 200 g of water while stirring. The mixturewas further stirred while in a dispersed state. Thirty minutes later,5.0 g of sodium chloride was added, and the stirring was continued for10 minutes to form a brown precipitate, which weighed 7.4 g. Thesphingoglycolipids content of the precipitate was 0.24 g as measured byHPLC. After washing with water, the extract had a sphingoglycolipidspurity of 3.2 wt %. The washing operation was repeated once more to give6.9 g of a precipitate, which was found to have a sphingoglycolipidscontent of 0.22 g as a result of HPLC. The purity of thesphingoglycolipids obtained after washing twice was 3.2 wt %. Theresulting product containing sphingoglycolipids of rice bran origin waspurified twice by silica gel column chromatography in the same manner asin Example 16 to obtain 28 mg of a sphingoglycolipids-containing producthaving a sphingoglycolipids content of 98.2 wt %.

[0116] The above-described series of operations were repeated severaltimes. The thus produced product containing sphingoglycolipids of ricebran origin (50.9 mg) was put into 10 ml of water while stirring anddispersed by 30-minute ultrasonication by use of BRANSON 3200, availablefrom Yamato Scientific Co., Ltd. The resultingsphingoglycolipids-containing aqueous dispersion was uniform andgenerated no sediment after one-day standing. This aqueous dispersioncontained 50 mg of sphingoglycolipids of rice bran origin.

Test Example 5 Influences on SC Water Content

[0117] The skin SC water content improving effects of the cosmetics ofthe invention obtained in Examples 16 and 17 and the aqueous dispersionsobtained in Comparative Examples 8 and 9 were tested with cooperation often female volunteers suffering from dry skin (five persons between theages of 20 and 40 and five persons between the ages of 40 and 60). Thetest persons were asked to apply 0.5 ml of each aqueous dispersion onthe inner side of the left upper arm for consecutive 30 days each. Theskin SC water content of the inner side of the left upper arm wasmeasured with Corneometer after 10 days, 20 days and 30 days. Theresults obtained are shown in Table 5 together with the results ofcontrol (the skin where the dispersion was not applied). TABLE 5 InitialAfter 10 After 20 After 30 Value Days Days Days Example 16 (tobiko 47 6575 78 powder origin) Example 17 (potato origin) 48 63 71 73 Compara.Example 8 48 58 60 60 (wheat flour origin) Compara. Example 9 (rice 4558 62 64 bran origin) Control (no application) 49 45 47 46

[0118] It can be seen from Table 5 that applying sphingoglycolipids ofkonjac tobiko powder origin or potato peel origin produces excellenteffects of improving SC water content of the skin.

Example 18 and Comparative Example 10 Preparation ofSphingoglycolipids-Containing Beauty Lotion

[0119] A beauty lotion containing sphingoglycolipids of konjac tobikopowder origin was prepared according to the formulation shown in Table 6below (Example 18). A beauty lotion was prepared according to the sameformulation except for the sphingoglycolipids (Comparative Example 10).TABLE 6 Sphingoglycolipids-containing product of Example 16 0.5 wt %(sphingoglycolipids concentration: 98.9%) Propylene glycol 4.0 wt % 70%Sorbitol solution 3.0 wt % Ethanol 5.0 wt % Perfume 0.1 wt % Methylp-hydroxybenzoate 0.1 wt % Sodium citrate 0.2 wt % Purified waterbalance

Test Example 6 Improvement on Feel of Use

[0120] The beauty lotions obtained in Example 18 and Comparative Example10 were organoleptically tested by twenty females for evaluating thefeel on application for 2 months. The results are shown in Table 7.TABLE 7 Duration Make-up Make-up Skin Overall of feel of Wear- Dura-Skin Elas- Flexi- Judge- moisture ability bility ticity bility mentExam- 37 30 32 35 37 38 ple 18 Com- 28 28 31 26 26 27 para. Exam- ple 10

[0121] Answers to Questionnaire and Scores:

[0122] 2 . . . Considerably good

[0123] 1 . . . Slightly good

[0124] 0 . . . Not good

[0125] The figures in Table 7 are total scores.

[0126] It is seen from Table 7 that the beauty lotion containingsphingoglycolipids of konjac tobiko powder origin exhibits excellenteffects in duration of moisture feel, skin elasticity and skinflexibility.

[0127] Industrial Applicability:

[0128] The sphingoglycolipids-containing functional foods and cosmeticsaccording to the present invention contain sphingoglycolipids, whichexist in human skin and seem to play an important role in moistureretention, in a high concentration and produce excellent effects inimproving the SC water content of human skin and improving rough skin,atopic dermatitis, allergic dermatitis, pimples, and so forth. Accordingto the production method according to the invention,sphingoglycolipids-containing functional foods and cosmetics can beproduced easily and economically by using as raw materials konjac tobikopowder, potato peel, oil cakes, etc. that have not been utilized as foodat all.

[0129] While the invention has been described in detail and withreference to specific examples thereof, it will be apparent to oneskilled in the art that various changes and modifications can be madetherein without departing from the spirit and scope thereof.

[0130] This application is based on Japanese Patent Application Nos.2000-219087 filed Jul. 19, 2000, 2001-021947 filed Jan. 30, 2001,2001-087695 filed Mar. 26, 2001, and 2001-188393 filed Jun. 21, 2001,which are incorporated herein by reference.

1. A functional food comprising a sphingoglycolipid derived from atuberous and corm vegetable or oil cake.
 2. A functional food comprisinga sphingoglycolipid and a plant sterol.
 3. A functional food accordingto claim 2, wherein said sphingoglycolipid is extracted from a tuberousand corm vegetable or oil cake.
 4. A functional food according to claim1 or 3, wherein the tuberous and corm vegetable is konjac.
 5. A cosmeticcomprising a sphingoglycolipid derived from a tuberous and cormvegetable or oil cake.
 6. A cosmetic according to claim 5, wherein thetuberous and corm vegetable is konjac.
 7. A method of producing afunctional food or a cosmetic according to any one of claims 1 and 3 to6, which comprises the steps of adding an organic solvent to a tuberousand corm vegetable or oil cake and extracting a sphingoglycolipid.
 8. Amethod of producing a sphingoglycolipid-containing product, whichcomprises the steps of adding an organic solvent to a tuberous and cormvegetable or oil cake and extracting a sphingoglycolipid.